In general, financial institutions have automated most check processing systems by printing financial information, such as account numbers and bank routing numbers, onto the checks. Before a check amount is deducted from a payer's account, the amount, account number, and other important information must be extracted from the check. This highly automated form of extraction is done by a check processing control system that captures information from the Magnetic Ink Character Recognition (“MICR”) line. The MICR line consists of specially designed numerals that are printed on the bottom of a check using magnetic ink. The MICR data fields include the bank routing number, bank transit number, account number, check serial number, check amount, process code and extended process code.
Checks and other documents may be processed by banks and other financial institutions in large numbers. The documents that may be processed might include checks, deposit slips, payment slips, etc. In some cases the banks or other financial institutions may be required to use the actual physical documents. For example, checks might need to be transported between multiple banks or other financial institutions. This may slow down the processing of financial documents. In addition, other types of documents that are non-financial in nature may be processed by businesses and other institutions in large volumes.
In order to facilitate processing of a document depicted in an image captured by a mobile device, image optimization and enhancement processing operations must be applied such that data can be extracted from the document. One approach to processing images captured from a mobile device is described in U.S. Pat. No. 7,778,457 to Nepomniachtchi et al., hereby incorporated by reference.
Nepomniachtchi et al. discloses either performing multiple image processing steps on a mobile device or transmitting large color images to a server. Mobile devices are often limited in terms of available processing power and transmission bandwidth. Performing multiple image processing operations on a mobile device can may take a long time due to the limited processing power and prevent the user from effectively performing other tasks on the mobile device. Similarly, sending images with a large file size will also take a long time and limit the communication functions of the mobile device while the image is being transmitted.
Nepomniachtchi et al. also discloses an algorithm for binarizing an image that applies the same algorithm to the entire document. Unfortunately, many images present complex backgrounds or weak image foregrounds (some foreground pixels have gray values very close to those of some background pixels). In such cases, it is not possible to find a single threshold or window that completely separates the foreground image from the background. This results in background noise in the bi-tonal image. In addition, certain document fields may be read by a computer process such that these areas should have limited background noise.
Nepomniachtchi et al. also discloses a system and method for correcting the upside-down orientation of a check within an image that relies on comparing MICR confidence from the original image with MICR confidence from a 180 degree rotated image. Relying on comparing MICR confidence readings limits the speed of the algorithm when implementing the method on a server with multi-threading/multi-processors. The approach in Nepomniachtchi et al. does not address cases where MICR confidence of both images is too low to be acceptable for subsequent processing.
Nepomniachtchi et al. also discloses a system and method for correcting the size of an image using the width of MICR characters. Using width of MICR characters may produce inaccurate size transformations since geometric correction can distort the shape of the MICR characters. Nepomniachtchi et al. also relies on the aspect ratio of the geometrically corrected image which may also be slightly distorted. It can also be difficult to discern the width of certain MICR characters compared to others. Nepomniachtchi et al. also does not scale the document to correspond to known or expected document or check dimensions.